1. Field of the Invention
The present invention relates to a method of measuring an immunoreactant using electrochemiluminescence.
2. Description of the Prior Art
Heretofore, it is known for measurement of an immunoreactant such as antigen or antibody in a liquid sample, to allow the immnoreactant to react with a complementary immnoreactant (antibody or antigen) which has been previously labeled with an electrochemiluminescent substance such as luminol or pyrene. The antigen-antibody reaction occurring between the two immnoreactants suppresses the electrochemiluminescence of the electrochemiluminescent substance labeled on the reacted complementary immunoreactant. Thus, it is possible to measure the concentration of the immunoreactant in the liquid sample by measuring reduction in emission of the electrochemiluminescent light (Y. Ikariyama et al., Biochem. Biophys. Res. Commun., 128, 987 (1985)).
However, the above technique has a defect that the rate of change in emission of the luminescent light depending on the change in the concentration of the antibody to be detected is small, and therefore accuracy of the measurement is low.